New in version 2.0.
True when notes in expr are stepwise descending:
abjad> from abjad.tools import tonalitytools
abjad> notes = [Note("c'8"), Note("d'8"), Note("e'8"), Note("f'8")]
abjad> t = Staff(list(reversed(notes)))
abjad> tonalitytools.are_stepwise_descending_notes(t[:])
True
Otherwise false:
abjad> tonalitytools.are_stepwise_descending_notes(Note("c'4"), Note("c'4"))
False
Changed in version 2.0: renamed tonalitytools.are_stepwise_descending() to tonalitytools.are_stepwise_descending_notes().